HSC Section 3 - Trauma, Critical Care and Sleep Medicine

Head and Neck Reconstruction

the incidence of hypertrophic scarring, thereby improving cosmetic outcome. Amniotic mem- brane adheres and conforms well to the contours of the face, and has low antigenicity and good anti- microbial potential. It, too, has been shown to in- crease rate of re-epithelialization. 9,10 Management of Full-Thickness Burns of the Head and Neck Historically, full-thickness burns of the head and neck region were treated with dressing changes until spontaneous separation of the eschar from underlying granulation tissue occurred. At this time, autografting on top of granulation tissue could be pursued. 12 This method often led to hy- pertrophic scarring because burns that heal after 21 days have greater than double the risk of hyper- trophic scarring compared with those that heal be- tween 14 and 21 days. 13 The concept of early tangential excision and grafting was introduced by Janzekovic 14 in 1970 and has become the treat- ment of choice in head and neck full-thickness burn injury as a way to minimize hypertrophic scar- ring and improve cosmetic outcomes. 15 Early exci- sion and sheet grafting yields results that permit the burn survivors to return to society and minimize the time off work or out of school. 16 Because it can be difficult on initial presentation to differentiate between partial-thickness and full- thickness burns of the head and neck, it is recom- mended to re-evaluate the wounds after 10 days. Most partial-thickness burns show signs of spon- taneous healing by this time. If the wound is not likely to heal by 21 days postburn, surgical exci- sion and skin grafting is recommended. 4,5,15,16 Burns that are clearly full-thickness are excised and skin grafted as soon as the patient’s medical status permits. The goal is to have the burn wound treated and skin grafted within 14 days of the burn injury. In panfacial burns, the eyelids should be excised first, followed by the nose, upper and lower lip, chin, cheeks, and then forehead. The eyebrows should be spared if spontaneous healing will preserve some hair in this area. In facial burn reconstruction, it is important to adhere to the aesthetic unit principle in which small, unburned areas of an aesthetic unit to be excised should be included at the time of resection and grafted as a whole. 4,17,18 Standard tools for tangential excision include the Goulian knife, the dermabrader, scratch pad, curette, and scalpel. Once the wounds have been excised and hemostasis achieved, many in- vestigators advocate a 2-stage approach to reconstruction with allograft placement before

skin grafting. Allograft is left in place anywhere from 48 hours to 1 week before skin grafting. The allograft acts as a test to determine if the wound bed is ready for autografting from a microbiology and a vascular consideration. If the allograft is adherent to the underlying wound, the burn has been adequately excised. If it is not, then that area of burn will require further excision or infec- tion treatment before autografting. 19 The Integra Dermal Regenerative Template (Inte- gra LifeSciences Corporation, Plainsboro, NJ, USA) is a bilaminar structure consisting of a layer of cross-linked bovine collagen and chondroitin- 6-sulfate. An outer silastic layer is also used in the first step toward reconstruction of burns of the head and neck. It is meshed and fixed to the wound bed after tangential excision is performed. Once it becomes vascularized, Integra forms a neodermis that is capable of accepting a much thinner autograft. This process takes approxi- mately 2 weeks before autografting is possible. Re- sults from the use of Integra and split-thickness skin grafts, have shown to produce acceptable co- lor match and texture with graft-graft junctures be- ing less evident. Newer formulations of Integra are thinner (without the silastic outer layer) and poten- tially allow for single-staged reconstruction of a more full-thickness–like graft. The use of Integra and delayed autografting on full-thickness eyelid burns, however, leads to ectropion and is, there- fore, not recommended. Full-thickness eyelid burns should be grafted immediately following tangential excision. 19 Thicker split-thickness skin grafts are generally preferred for the reconstruction of the head and neck, except when using Integra. Skin grafts are harvested at a thickness of 0.018 to 0.025 of an inch in adults and 0.008 to 0.012 of an inch in chil- dren. The thicker skin graft decreases the amount of secondary contracture that occurs during heal- ing. The scalp is the donor site of choice when available, followed by the upper back and chest, and, less frequently, the abdomen and thighs. 4 In the case of large total body surface area burns, grafts for the face are obtained wherever adequate skin is available and set aside before harvesting skin graft of the rest of the body. 16 Delayed treatment of full-thickness burns of the eyelids can lead to exposure keratitis and corneal ulceration because the wound contracts and ectropion ensues. Early eyelid release and skin grafting has been shown to reduce the incidence of these complications. Split-thickness skin grafts used for upper eyelid reconstruction fold and Treatment of Burns to the Eyelids and Ears

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